When writing a message to a user (in his profile or in “Incoming” section) you can choose the way of its sending.
By default, a message is always sent to a website, so a user can read it in his personal profile in “Messages” section.
There are the following available ways of messages sending:
Checkboxes are chosen for those ways, that notifications are active for in a personal profile in “Response for ticket to technical support team is received” item.
Length of a message in SMS is limited by 250 characters (the rest is cut off).
If there’s no way selected, then a message is sent to a website. A user can view it when going to his personal profile.